Suto Hirotaka, Inui Yumiko, Okamura Atsuo
Department of Medical Oncology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
Department of Medical Oncology/Hematology, Kakogawa Central City Hospital, Hyogo, Japan.
Front Oncol. 2023 Apr 20;13:1158797. doi: 10.3389/fonc.2023.1158797. eCollection 2023.
Response evaluation criteria in solid tumors version 1.1 (RECIST ver1.1) has been widely adopted to evaluate treatment efficacy in solid tumors, including breast cancer (BC), in clinical trials and clinical practice. RECIST is based mainly on computed tomography (CT) images, and the role of fluorodeoxyglucose-positron emission tomography (FDG-PET) is limited. However, because the rate of tumor shrinkage on CT does not necessarily reflect the potential remaining tumor cells, there may be a discrepancy between the treatment response and prognosis in some cases. Here we report a case of metastatic human epidermal growth factor receptor 2 (HER2)-positive BC where FDG-PET was preferable to CT for evaluation of the treatment response. A 40-year-old woman became aware of a lump in her right breast in September 201X. She was pregnant and underwent further examinations, including a biopsy, in November. The diagnosis was HER2-positive BC (cT2N2bM1, stage IV). Trastuzumab plus pertuzumab plus docetaxel (TPD) therapy was initiated in December 201X. CT performed in February 201X+1 showed cystic changes in the metastatic lesions in the liver, and the treatment response was stable disease (SD) according to RECIST. However, FDG-PET in March 201X+1 did not detect abnormal uptake of FDG in the hepatic lesions. The disease remained stable thereafter. Thus, tumor shrinkage may not be apparent in situations where the response to treatment results in rapid changes in blood flow within the tumor, which is associated with cystic changes. When patients with hypervascular liver metastases receive treatment with highly effective regimens, the target lesion may show cystic changes rather than shrinkage, as observed in the present case. Therefore, FDG-PET is sometimes superior to CT in judging a tumor response.
实体瘤疗效评价标准1.1版（RECIST ver1.1）已在临床试验和临床实践中被广泛用于评估实体瘤（包括乳腺癌（BC））的治疗效果。RECIST主要基于计算机断层扫描（CT）图像，氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）的作用有限。然而，由于CT上肿瘤缩小率不一定反映潜在的残留肿瘤细胞，在某些情况下治疗反应与预后之间可能存在差异。在此，我们报告一例转移性人表皮生长因子受体2（HER2）阳性乳腺癌病例，其中FDG-PET在评估治疗反应方面优于CT。一名40岁女性于201X年9月发现右乳有肿块。她当时怀孕，11月接受了包括活检在内的进一步检查。诊断为HER2阳性乳腺癌（cT2N2bM1，IV期）。201X年12月开始使用曲妥珠单抗加帕妥珠单抗加多西他赛（TPD）治疗。201X + 1年2月进行的CT显示肝脏转移灶有囊性改变，根据RECIST，治疗反应为疾病稳定（SD）。然而，201X + 1年3月的FDG-PET未检测到肝脏病变中有异常的FDG摄取。此后疾病保持稳定。因此，在治疗反应导致肿瘤内血流快速变化并伴有囊性改变的情况下，肿瘤缩小可能不明显。如本病例所示，当肝转移瘤血供丰富的患者接受高效方案治疗时，靶病灶可能表现为囊性改变而非缩小。因此，在判断肿瘤反应方面，FDG-PET有时优于CT。
